This invention relates to improved pedal actuated drive mechanisms of a unique type adapted for use in driving a bicycle, tricycle, pedal powered car, boat, sewing machine, wheel chair, power tool such as a lathe or grinder, washing machine, or any of various other types of mechanism to which the apparatus may be adapted. Certain features of the invention have been shown in Disclosure Document No. 022010 filed in the United States Patent Office Sept. 4, 1973.
There have in the past been devised pedal actuated drive mechanisms in which two pedal structures are mounted to swing in opposite directions, and act by this oscillatory swinging movement to drive one or more vehicle wheels. In one such mechanism of which I am aware, two flexible cables extend rearwardly from the two pedal structures, and act through two one-way clutches to drive a pair of vehicle wheels through a transmission, with each clutch exerting torque in a predetermined driving direction when the corresponding pedal is pressed by the user, and with the cable and pedal being spring returned in an opposite retracting direction when the foot pressure is released. One disadantage of this type of mechanism resides in the fact that on each active stroke of a pedal extra force must be exerted to overcome the torque of the retracting spring, and consequently the mechanism is not as efficient as would be desired. Further, this prior device has required a fairly complex and expensive transmission in order to alter the effective transmission ratio of the overall system. As a result, the cost of the assembly has been more than would be desired in a motorless vehicle.